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No. 750,471. PATENTED JAN. 26, 1904. L. LYNDON & E. A. SPERRY. SYSTEM OFELECTRICAL GENERATION, DISTRIBUTION, AND CONTROL.

APPLICATION FILED JAN. 17, 1903.

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No. 750,471. PATENTED JAN. 26, 1904.

L. LYNDON & E. A. SPEERY. SYSTEM OF ELECTRICAL GENERATION, DISTRIBUTION,AND CONTROL.

APPLICATION FILED JAN.17,1908.

4 SHEETSSHEET 2.

N0 MODEL.

No. 750,471. PATENTED JAN. 26, 1904.. L. LYNDON & E. A. SPERRY.

SYSTEM OF ELECTRICAL GENERATION, DISTRIBUTION, AND CONTROL.

APPLICATION FILED JAN. 17, 1903.

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No. 750,471. PATENTED JAN. 26, 1904. L. LYNDON & E. A. SPERRY. SYSTEM OFELEGTRICAL GENERATION, DISTRIBUTION, AND CONTROL.

APPLICATION FILED JAN.17, 1903. N0 MODEL. 4 SHEETS-SHEET 4.

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UNITED STATES Patented January 26, 1904.

PATENT OEEIcE.

LAMAR LYNDON, OF NEXY YORK, N. Y., AND ELMER A. SPERRY, OF CLEVELAND,OHIO, ASSIGNORS TO NATIONAL BATTERY COMPANY, OF JERSEY CITY, NEV JERSEY,A CORPORATION OF NElV JERSEY.

SYSTEM OF ELECTRICAL GENERATION, DISTRIBUTION, AND CONTROL.

SPECIFICATION forming part of Letters Patent No. 750,471, dated January26, 1904.

I Application filed January 17, 1903. Serial Nc. 139,399. (No model.)

To all whom, it may concern.-

Be it known that we, LAMAR LYNDON, resid ing in the borough ofManhattan, in the city of New York, in the State of New York, and ELMERA. SPERRY, residing in Cleveland, in the county of Cuyahoga, in theState of Ohio, citizens of the United States,have invented certain newand useful Improvements in Systems of Electrical Generation,Distribution, and Control, of which the following is a specification,reference being had to the accompanying drawings, forming a part hereof.

This invention relates to systems and apparatus for the generation,distribution, and control of electric current and has been developedmore especially with a view to the solution of difficulties incident tovariations in speed of the source of power by which the generator isdriven.

The particular application of the invention with reference to which itwas developed and in which it finds its concrete expression israilway-car lighting in which current is generated'thro'ugh the movementof a car or train, the generator being ordinarily driven from a caraxle. In such an application of the invention provision should be madeto maintain uniform strength of current notwithstanding considerablevariation in the speed of the car. The effect upon a system of areversal of the direction of movement of the car should be antici patedand accommodated. Provision should be made for discontinuing theoperation of the generator under conditions which are unfavorable to thecontinued generation of current through the movement of the car, as whenthe train approaches a terminal and takes the short radius curves,switches, and crossovers common in a terminal yard. The automatic supplyof current to the lighting-circuit of the car when the speed falls belowa predetermined rate should be provided for. The medium through whichthe automatic regulation and control of the various parts of the systemare effected should be of such a character as to be substantiallyunaffected by considerable variations in temperature and the otherconditions of use. The different various devices should be soconstructed as to be substantially unafl'ected by the vibrations andother conditions of use, and in general the system should be adapted toovercome difficulties incident to the character of the source of'powerand to the conditions under which the system is used. Devices by whichsome of these requirements are met are fully described and covered inthe application of Elmer A. Sperry, one of the present applicants,Serial No. 134,035, filed December 5, 1902, which is subordinate to thepresent application, wherein is covered the broad invention embodied inmechanical and electrical devices described in said application, SerialNo. 13 E035, so far as the same is the joint invention of the presentapplicants. The general object of the present invention is therefore thesame as that set forth in said application, Serial No. 13O35-viz., toproduce a system which will give thoroughly satisfactory results underall conditions of use, either for the lighting of railway-cars or forother analogous purposes.

It will be obvious that the general object can be attained and thegeneral features of construction and arrangement can be embodied by andin specific structures which differ more or less in detail. One of suchembodiments will be particularly described hereinafter with reference tothe accompanying drawings, in which it is illustrated, and in order thatthe functions of the several mechanical parts may be more readilycomprehended a general description of such embodiment of the inventionwithout reference to the drawings will now be presented. A

The generator or dynamo is driven, as by a belt, from one of thecar-axles, and in order that the slip of the belt may be taken advantageof to assist in the regulation of the electromotive force through thespeed of the dynamo a belt-tightener is provided for the purpose ofslackening or tightening the drivingbelt. The action of the belttightener to slacken or tighten the belt is controlled by the pressureof a suitable fluid medium, preferably an oil which will resist lowtemperatures, the pressure being developed by the action of a pumpdriven by a motor which is'in circuit with the dynamo or batteriessupported there by. A valve in the pipe system may be'suitablycontrolled, as by a solenoid or other electromagnetic device in circuitwith the dynamo to vary the pressure at the point where it performs itsWork in controlling the belt-tightener, whereby any variation in thevoltage of the current shall effect the movement of the belt-tightenerto tighten or slacken the belt, and thereby to correct the variation inthe voltage and restore it to the normal. The motor for driving the pumpis also subject to the control of the pressure of the fluid medium, sothat its operation shall cease when the pressure rises above apredetermined degree and shall be resumed automatically when thepressure falls below a predetermined degree. To compensate for variationin the electrical translating devices, as in the number of lights incircuit, so that the voltage of the current supplied to the remaininglights shall remain substantially uniform, and to compensate forvariations in voltage of battery or dynamo, suitable resistance isincluded in the circuit and means are provided for throwing in or outmore or less of such resistance, such means being operated by thepressure of the fluid medium and controlled by the action of a solenoidor other electromagnetic device ineluded in circuit with the lamps. Astorage battery is to be included in the circuit in order that thenecessary lighting current may be provided when the car is stationary orthe speed of the car falls below a predetermined minimum.

In the accompanying drawings, wherein is illustrated the particularembodiment of the invention chosen for explanation, Figure 1 is anoutline, in side elevation and partly broken out, of a railway-carequipped with the invention embodied in a lighting system. Fig. 2 is adiagrammatic view illustrating the general relation of the severalmechanical and electrical elements of the system in the same applicationthereof. Fig. 3 is a view, partly in elevation and partly in verticalsection, illustrating the means for controlling the slip of the belt bywhich the dynamo is driven. Fig. 4: is a detail View, on a larger scale,of a portion of the belt-tightener with the dynamo and itsdriving-pulley. Fig. 5 is a view in vertical section of the solenoid andvalve operated thereby for controlling the pressure upon the pistonshown in Fig. 3. Fig. 6 is a view in vertical section on the planeindicated by the line 6 6 of Fig. 8, showing the pump. Fig. 7 is a viewin vertical section on the plane indicated by the line 7 7 of Fig. 8,illustrating the device for starting and stopping the pumpautomatically. Fig. 8 is a horizontal section on the plane indicated bythe line 8 8 of Figs. 6 and 7. Fig. 9 is a view in vertical Fig. 10 is aview in horizontal section on the plane indicated by the line 10 10 ofFig. 9. Fig. 11 is a view in vertical section of the solenoid and thevalve operated thereby for controlling the pressure upon the plungershown in Fig. 9. Fig. 12 is atop plan view of the parts shown in Fig.11.

The dynamo (indicated at a) may be of any suitable construction and issupported beneath the car-floor or in any other convenient location. Itmay have a driven pulley a mounted on its shaft (1/ and be driven by abelt (0 from a driving-wheel b on the car-axle. For the purpose ofcontrolling the speed, and therefore the electromotive force, of thedyname through the friction of the driving means suitable mechanicaldevices may be provided, such as a belt-tightener, which is arranged toact upon the belt and is itself controlled by devices presently to bedescribed. he particular construction of the belttight ener forms nopart of the present invention, and for a detailed description of thebelt-tightener shown in the accon'ipanying drawings reference may be hadto the aforesaid application, Serial No. 13 1,0235. For the purposes ofthe present case it is sufiicient to say that a frame or ring 0 ismounted to oscillate or swing upon a circular flange a of the dynamoeasing, said frame having a pin or stud 0, upon which is mounted anidler 0, adapted to rest against one side of the belt. To the frame 0 ispivoted an arm 0 also having a pin or stud c", carrying an idler 0,adapted to rest against the other side of the belt. The mechanicaldevices for acting upon the belttightener to slacken or to tighten thebelt are mounted upon the frame 0 and are adapted to increase ordiminish the distance between the two idlers 0 and 0".

One object of the invention being to provide for the operation of thebelt-tightener by a fluid medium, the mechanical devices for operatingthe belt-tightener comprise a cylinder (Z, which is fixed upon theoscillating frame 0, as indicated above, and a piston (.Z in saidcylinder and connected by suitable link (l with the arm 0 the fluidmedium, under pressure from a suitable source, being admitted to thecylinder behind the piston. Oil of a suitable quality placed underelastic pressure by a suitable pump is the most satisfactory medium forthe transmission of the required power to the mechanical element, suchas the piston d, by which the tightening of the belt is effected,lending itself most readily to the peculiar requirements of the case,the belt-regulating devices thus becoming sensitive and quicklyresponsive in operation,while acting with certainty under conditions ofconstant and excessive vibration and of widely varying temperatures.Furthermore, such devices are readily controlled through variations ofthe voltage of the current produced by the dynamo, so that suchcurrentis generated as required and remains substantially uniformnotwithstamling considerable variations in the speed of movement of thecar. The cylinder cZ accordingly is connected by a suitable pipesystem,in clud ing sections (Z and (Z*, which are movable to accommodatethe movement of the cylinder with the frame 0, and a fiXed section CZ",with an oil-pressure tank (Z and a pump 6, operated by a motor f, whichis in circuit with the translating devices and the'storage batteryhereinafter referred to. The tank (Z may be an ordinary tight tank,having a single inlet for connection with the pipe system (Z andpreferably contains a volume of air which acts as an elastic cushion forthe oil which is delivered by the pump 6. The latter is placed inconvenient relation to an oil-pan g, which contains the supply of oiland receives the oil through the return-pipes from the several actuatingdevices, the pump being preferably mounted above the oil-pan at anyconvenient point within the car and being of ordinary construction,comprising a reciprocating plunger 0, an inlet-valve eiand anoutlet-valve 0 the discharge being connected with the pipe system (Z Theplungere may be connected by a pitman a with a crank or crank-pin (2carried by the shaft of a gear a, which is in mesh with a driving-pinionf on the shaft of the small motor provided for the operation of thepump. lWleans are provided whereby the operation of the pump shall bedependent upon the pressure on the fluid medium, the pump beingautomatically thrown out of operation when the pressure rises above apredetermined degree and also thrown into operation when the pressurefalls below a predetermined degree. It is desirable to provide for adirect control of the pressure on the piston-head (Z by variations inthe voltage of the current. To this end a solenoid 7b is included incircuit with the dynamo. its core it is statically balanced, beingconnected by a lever 7L with a counterweight 71 so that the core shallnot be affected by the vertical vibrations or the car, and also with anadjustable spring 7b, which opposes the pull of the solenoid upon thecore. The core of the solenoid controls a valvecf, interposed in thepipe system, by means of which admission of oil to the cylinder (Z isregulated and bywhich the oil in the cylinder may be in part releasedand permitted to return to the oil-pan, so that the belt may slacken. Asshown, the valve comprises a plug or stem (Z turned down, as at (.Z", toform a passage between the head and the body of thevalve. Thevalve-chamber has a port (Z communicating with the pressure-tank, a port(Z communicating with the cylinder (Z, and a port (Z13, communicatingwith the oil-pan through a return-pipe c The valve is shown in its normal position, the port (Z being closed. If

now the voltage of the current increases, the core will be raised sothat the head (Z of the valve shall be moved to establish connectionbetween the port (Z and the port 0Z thereby relieving the pressurebeneath the piston (Z in the cylinder (Z and permitting the belt toslacken, and therefore to slip, whereby the speed of the dynamo isreduced. If, on the other hand, the voltage of the current decreases,the spring it draws down the core 71/, thereby moving the valve-plug (Zto establish communication through the channel (Z between the ports (Zand (Z thereby permitting more oil to pass into the cylinder (Z, andthereby to tighten the belt and increase the speed of the dynamo.

It will be understood that the ordinary finewire winding 7i of thesolenoid i1, is included in a shunt from the main circuit of the dynamo. Under some circumstances, as when a great quantity of current isflowing over the circuit, it is desirable to assist the fine winding ofthe solenoid in its action upon the core to open the valve and relievethe pressure behind the belt-controlling piston in order that the dynamomay be checked and abnormal overload and consequent burning outprevented. Accordingly a winding if of coarse wire is first laid, up anddown, about the sleeve of the solenoid and is connected in series withthe armature-winding of the d ynamo. A resistance may be thrown acrossthe connections of this coarse winding and when the quantity of currentrises to a predetermined degree, for which the windings of the solenoidand the resistance are duly proportioned, the coarse winding will assistthe fine winding and insure the prompt opening of the valve and theconsequent checking of the dynamo. This particular device forms no partof the present invention, which contemplates the connection of thesolenoid or its equivalent in the circuit in any manner suitable to theaccomplishment of the intended purpOSG.

Whether any other device be employed to regulate the pressure in thecylinder (Z, as above described, or not, it is desirable to providemeans, as above suggested, whereby the pump shall be stopped wheneverthe pressure on the fluid medium increases above a predetermined maximumand shall be started again whenever the pressure falls below apredetermined minimum. To accomplish this, a pressure relay device, asshown in Figs. 7 and 8, is employed. This device comprises a cylinder1:, having a plunger 2:, moved in one direction by an adjustable springThe cylinder 2' is in communication with the pipe system (Z so that theplunger 2" is shifted by variations in the pressure, and the plungercontrols a valve (Z iwhich may be in all respects the same as the valve(Z the same reference-letters be ing employed to indicate like parts.The port (Z .of the valve (Z is in communication with the pressure-tank,the port (Z is in communication with the return-pipe (Z and the port (Zis in communication with a cylinder 7 in which is a plunger Z", adaptedto be moved in described.

one direction by the pressure in the cylinder and in the oppositedirection by a spring The stem 70 of the plunger is operativelyconnected with a switch it in the branch of the circuit which includesthe motor f, the switch being opened when the plunger it" moves downwardunder the influence of the spring 70 and being closed as it is movedupward by the pressure of the fluid medium in the cylinder 75. It willnow be understood that when the pressure in the pressure-tank increasesabove the predetermined maximum the plunger a" will be moved upwardagainst the spring 71 thereby permitting the pressure beneath theplunger k to be relieved by the movement of the valve-plug at, whichestablishes communication between the ports (Z and c On the other hand,if the pressure in the system falls below the predetermined minimum theplunger 2" will descend against the reduced pressure in the cylinder 7?,moving the valveplug (Z downward to establish communication between theports (Z and (Z thereby admitting the fluid medium to the cylinder 71;and raising the plunger 70 to close the switch 7& and start up the pumpagain. Anon-centering spring 73 is connected to the switch to retain theswitch and the plunger in their extreme positions, lost motion beingprovided for between the plunger and the switch, as by a slot-and-pinconnection, as at 77 to facilitate the quick movement of the switch.

In order that the voltage of the current supplied to the lamps shall besubstantially uniform notwithstanding variations in the number of lampsin use or in the current supplied by the dynamo or batteries, or both,and especially to utilize the full range of the battery voltage, it isdesirable to include in the lampcircuit a variable resistance, theamount of resistance included being controlled automatically. Asrepresented in the drawings, Figs. 2, 9, 10, 11, and 12, the devicecomprises an ordinary variable resistance Z, a movable contact-arm m,and mechanical devices electrically controlled and actuated for shiftingthe arm m. As represented in the drawings, a solenoid a is included inthe main circuit, while its core a is statically balanced, beingconnected by a lever 02/ with a counterweight n in order that the coremay not be affected by vibrations and with an adjustable spring 02.,which opposes the action of the solenoid. The core is operativelyconnected with a valve (Z which is in all respects similar to the valve6?, heretofore The parts of the valve (Z16 are indicated by like lettersof reference, and no detailed description of the valve is necessary. Theport (Z is in communication with the pressure system and the port (Zwith the re turn-pipe system d, while the port el is in communicationwith a cylinder 0, in which is disposed a plunger 0. A rack 0 carried bythe plunger, engages a pinion 0 on the shaft 0", which carries themovable resistance-arm m. A coil-spring 0 be applied to the shaft 0 tooppose the pressure in the cylinder 0 and restore the parts to normalposition when the pressure therein is reduced. It will be understoodthat when the voltage increases the core at will be drawn up, and thevalve (Z will be operated to connect the cylinder 0 with the return-pipesystem (i through the ports (Z and (Z thereby permitting the plunger todescend and the arm on. to be moved to include more resistance in thelamp-circuit, and that if the voltage falls the spring a will cause thecore to move downward, actuating the valve (Z to admit pressure to thecylinder 0 through the ports (Z and ti, thereby moving the plunger andthe arm m in a direction to reduce the amount of resistance included inthe circuit.

A storage battery 9' is arranged to be included in circuit to maintainthe lights when the car is stationary or moves at a speed less than thepredetermined minimum. It may be recharged from the dynamo, andprovision is made whereby the dynamo shall be cut out when the currentgenerated is less than supplied by the battery. To this end a switch a,having a member in each leg of the main circuit, may be arranged to becontrolled by a differential magnet t, the armature t of which isoperatively connected with the switch and has attached a spring t toopen the switch when the armature is released by the magnet. One set, t,of the coils of the magnet is included in a shunt from the main circuitand energizes the magnet to hold the armature normally up with theswitch closed. The other set, 6', of the coils of the magnet is includedin one leg of the main circuit in series with one of the switch members,the coils being wound in the same direction as those of the set t Thusif the electromotive force of the current from the battery exceeds thatof the current from the dynamo the rush of current backward through thecoils t" will neutralize the effect of the coils 6 upon the core of themagnet and permit the armature to drop. When the electromotive force ofthe dynamo is increased sufficiently, the coils 2?, included in theshunt, will energize the magnet sufliciently to again attract thearmature and restore the connection between the dynamo and thelamp-circuit.

The operation of the system will be understood from the foregoingdescription without further explanation.

It will be understood that such of the details of the electrical andmechanical devices herein described as are claimed in the afore saidapplication, Serial No. 134,035, and are not claimed in this applicationhave been illustrated and explained herein merely as convenient andpractical embodiments of the main features of the invention and can bereplaced by other devices of like general nature and operating toproduce similar results which will readily suggest themselves. It willalso be understood that it is not intended to limit the invention,except as may be pointed out in the claims hereinafter, to anyparticular construction or arrangement of devices necessary toaccomplish the results herein pointed out.

e claim as our invention l. The combination of a variable power source,an electric generator, a variable power transmission between the powersource and the generator, fluid-pressure-operated devices for varyingthe transmission of power, and electrically-actuated devices in thecircuit and including a statically-balanced moving element forcontrolling said devices.

2. The combination of a variable power source, an electric generator, avariable power transmission between the power source and the generator,fluidpressure-operated devices for varying the power transmission, atwoway valve for controlling said devices, and electrical devices in thecircuit to actuate said valve.

3. The combination of a variable power source, an electric generator,avariable power transmission between the power source and the generator,fiuid-pressure-operated devices for varying the power transmission, abalanced valve to control said devices, and electrical devices in thecircuit to actuate said valve.

4:. The combination of a variable-speedpower source an electricgenerator, a variable-friction power transmission between the powersource and generator, fluid-pressureoperated devices for varying thefriction, and electrically-actuated devices in the circuit and includinga statically-balanced moving ele ment for controlling said devices.

5. The combination of a variable-speedpower source, an electricgenerator, a variablefriction power transmission between the powersource and the generator, fluid-pres sure-operated devices for varyingthe friction, a two-way valve for controlling said devices, andelectrical devices in the circuit to actuate said valve.

6. The combination of a variable-speedpower source, an electricgenerator, a variable-friction power transmission between the powersource and the generator, fluid-pressure-operated devices for varyingthe friction, a balanced valve to control said devices, and electricaldevices in the circuit to actuate said valve.

7. The combination of a power source, an electric generator, a variablepower transmission, electric translating devices, a currentcontrollerbetween the translating devices and the generator, actuating devices forboth the current-controller and the variable power transmission, and acommon source of power for said actuating devices.

8. The combination of a power source, an

electric generator, avariable power transmission, electric translatingdevices, a currentcontroller between the translating devices and thegenerator, actuating devices for both the current controller and thevariable power transmission, a common source of power for said actuatingdevices, and a motor for said source of power in circuit with thetranslating devices. I

9. The combination of a source of power, an electric generator, avariable power transmission, electric translating devices, acurrentcontroller between the translating devices and the generator,actuating devices for both the current controller and the variable powertransmission, and electrical devices in the circuit to control theactuating devices.

10. The combination of a source of power, an electric generator, avariable power transmission, electric translating devices, acurrentcontroller between the translating devices and the generator,actuating devices for both the currentcontroller and the variable powertransmission,and statically-balanced electrical devices in the circuitto control the actuating devices.

11. The combination of a power source, an electric generator, avariable-speed power transmission, electric translating devices, acurrent-controller between the translating devices and the generator,fluid-pressure-actuating devices for both the current-controller and thevariable power transmission, and a common source of fluid-pressure forsaid actuating devices.

12. The combination of a power source, an electric generator, avariable-speed power transmission, electric translating devices, acurrent-controller between the translating devices and the generator,lluid-pressure-actuating devices for both the current-controller and thevariable power transmission, a common source of power for said actuatingdevices, and a motor for said source of power in circuit with thetranslating devices.

13. The combination of a source of power, an electric generator, avariable-speed power transmission, electric translating devices, acunent-controller between the translating devices and the generator,fluid-pressure-actuating devices for both the current-controller and thevariable power transmission, and electrical devices in the circuit tocontrol the actuating devices.

1 1. The combination of a source of power, an electric generator, avariable-speed power transmission, electric translating devices, acurrent-controller between the translating devices and the generator,fluidpressure-actuating devices for both the current-controller and thevariable power transmission, and statically-balanced electrical devicesin the circuit to control the actuating devices.

15. The combination of a power source, an electric generator, avariable-power-transmis- IIO sion device for the generator, devices inoperative relation with the generator to establish fluid-pressure, meansoperated by the fluid-pressure to control the variable-powertransmissiondevices, electrical actuating means for said fluid-pressure devices andcircuit connections between the generator and the electrical actuatingmeans.

16. The combination of a power source, an electric generator, avariable-power-transmission device for the generator, devices inoperative relation with the generator to establish fluid-pressure, andmeans operated by the fluid-pressure to control the variable powertransmission, electrical actuating means for said fluid-pressure devicesand shunt connections between the generator and the electrical actuatingmeans.

17 The combination of a power source, a shunt-wound electric generator,a variabletransmission device for the generator, devices in operativerelation with the generator to establish fluid-pressure, and meansoperated by the fluid-pressure to control the variable powertransmission, electrical actuating means for said fluid-pressure devicesand circuit connections between the generator and the elec tricalactuating means.

18. The combination of a power source, an electric generator, avariable-power-transmission device for the generator, devices inoperative relation with the generator to establish fluidpressure, andmeans operated by the fluid-pressure to control the variable powertransmission, electrical actuating means for said fluid-pressuredevices, circuit connections between the generator and the electricalactuating means, and a storage battery in circuit with the generator.

19. The combination of an electric generator, avariable-p0wer-transmission device for the generator, devices inoperative relation with the generator to establish fluid-pressure, andmeans operated by the fluid-pressure to control the variable powertransmission, electrical actuating means for said fluid-rn'essuredevices, circuit connections between the generator and the electricalactuating means, a storage battery in circuit with the generator, and aswitch between the generator and the battery.

20. The combination of a source of power, an electric generator, avariable-power-transmission device for the generator,electricallyactuated devices in operative relation with the generator toestablish fluid-pressure, and means operated by the fluid-pressure tocontrol the variable power transmission, electrical actuating means forsaid fluid-pressure devices, circuit connections between the generatorand the electrical actuating means, a storage battery in circuit withthe generator, a switch between the generator and the battery, andelectrical devices included in the circuit to control said switch.

21. The combination of a group of electric translating devices, astorage battery, an electric generator, a variable-speed-power sourcefor the generator, means for controlling the speed of the generator, aswitch between the generator and battery, a rheostat between thegenerator and the translating devices, means to operate said switch andsaid rheostat, and electrical devices included in the circuit to controlthe operation of said speed-controlling means.

This specification signed and witnessed this 15th day oi January, A. D.1903.

LAMAR LYNDON. ELHER A. SPERRY.

In presence of Looms E. VARNEY, RoswnLL S. NICHOLS.

